In fact, it was during my PhD studies that I came upon the work of Williamson and refer to it frequently in several papers etc.. Essentially the transaction cost economics approach suggests that you stay with the same supplier, to reduce the costs of finding new suppliers and improve the supply chain performance. The subsequent theory development by a variety of scholars in marketing,supply chain,law, organization, strategy and off course economics continue to look at different questions at the "boundary of the firm" aka B2B and Supply Chain.
Here is a rather long press conference video from UC Berkley with Professor Williamson. About halfway down the video (20 minutes) a reporter asks whether the Nobel committee finally recognized him after the global financial crisis where buyer seller relationships had become too cosy and the mortgage mess escalated. This blog has been discussing these inter-organizational issues for the past year and celebrates the timely award to Professor Williamson.